Resist composition for supercritical development

Abstract

In a resist composition for supercritical development process, a development process is carried out by supercritical development process without alkali development process, and includes a base resin which is not removed by said supercritical developer in the presence of acid (A) and an acid generator which generates an acid upon activation by light or electromagnetic waves (B).

1 . A resist composition for supercritical development process for forming a resist pattern wherein exposed resist film was treated with a supercritical developer comprising a supercritical fluid to allow the unexposed region of said exposed resist film to be selectively removed, said composition comprises:
 a base material resin which is not removed by said supercritical developer in the presence of acid (A); and   an acid generator which generates an acid upon activation with at least one of lights and electromagnetic waves (B).   
   
   
       2 . The composition according to  claim 1  wherein said supercritical fluid comprises carbon dioxide and quarternary ammonium salts. 
   
   
       3 . The composition according to  claim 1  wherein:
 said base resin (A) includes a polymer having a constituent unit (a 1 ) represented by the following general formula (I); and   at least a part of hydrogen atoms of the hydroxyl groups of said constituent unit (a 1 ) are substituted by at least one of an acid-dissociable group represented by the following general formula (II) and the following general formula (III).   
     
       
         
         
             
             
         
       
     
     wherein R 1  represents a hydrogen atom or a methyl group. 
     
       
         
         
             
             
         
       
     
     wherein
 R 2  and R 3  each independently represent an alkyl group having 1 to 5 carbon atoms or a hydrogen atom, and 
 X represents any one of the groups selected from the group consisting of an alkyl group having 1 to 5 carbon atoms, an aliphatic polycyclic group, and an aromatic polycyclic hydrocarbon group. 
 
     
       
         
         
             
             
         
       
     
     wherein
 Y represents any one of the groups selected from the group consisting of an alkyl group having 1 to 5 carbon atoms, an aliphatic polycyclic group, and an aromatic polycyclic hydrocarbon group 
 
   
   
       4 . The composition according to  claim 1  wherein said polymer included in said base resin (A) further comprises a constituent unit (a 2 ) represented by the following general formula (IV) 
     
       
         
         
             
             
         
       
     
     wherein
 R 4  represents a hydrogen atom or a methyl group, 
 R 5  represents an alkyl group having 1 to 5 carbon atoms, and 
 n represents an integer of 0 or 1 to 3. 
 
   
   
       5 . The composition according to  claim 1  wherein one of at least said X and Y are adamantyl group or naphthyl group. 
   
   
       6 . The composition according to  claim 1  wherein the content of said acid generator (B) is from 5 parts by mass to 30 parts by mass per 100 parts by mass of said base resin (A). 
   
   
       7 . The composition according to  claim 1  which further comprises a basic compound (C). 
   
   
       8 . The composition according to  claim 1  wherein the content of said basic compound (C) is from 0.1 part by mass to 20 parts by mass per 100 parts by mass of said base resin (A). 
   
   
       9 . The composition according to  claim 1  wherein said basic compound (C) is secondary or tertiary amine having alkyl groups having 7 to 15 carbon atoms. 
   
   
       10 . The composition according to  claim 1  which further comprises an organic acid (D) in an amount of 0.1 part by mass to 20 parts by mass per 100 parts by mass of said base resin (A).